The present invention relates to railway vehicles having a combined body bolster center filler and center plate, such as is shown in U.S. Pat. No. 3,664,269, and more particularly to an improved center plate.
The center plate assemblies currently in use today comprise a center plate portion which is welded to the underedge of the center sill pocket walls. A vertical spacer plate for withstanding the shear and vertical forces imposed thereat is rigidly secured and located longitudinally within the sill at each opposite end of the center plate. A separate tie plate horizontally spanning and secured to the sill pocket exterior of the center plate and connected to the underedge of each spacer plate provides stiffening reinforcement and distributes longitudinal center plate forces to the car sill. The center plate projects from the car center sill pocket at least a distance which is equal to: the corresponding truck center plate depth ("bowl depth"), the thickness of the positioning lugs which rest on the exposed surface edges of the sill and spacer plates, and the height of the transition radius between the positioning lug and the vertical wall of the center plate. Specially applied lugs have been necessary to ensure that the center plate is properly oriented.
The Federal Railroad Administration and the American Association of Railroads (AAR) require that all railway cars must be able to couple with each other. Accordingly, for a standard coupler, which extends from the car center sill, a height range of 31 inches to 34 inches has been set for American railway cars. Car builders have found it difficult to meet this upper standard, especially when their railway vehicles are initially offered due to high-end tolerances of various components such as the stiffness of new springs prior to settling, wheels only being furnished as oversized (with plus tolerances), etc.
Furthermore, lower coupler heights are desirable since this also results in a lower center of gravity in the railway vehicle which makes the vehicle less apt to tip. Hence, any modifications made to the center plate which result in coupler height reduction are very important to the car building industry.